What is a garage conversion?
A garage conversion turns an integral or attached garage into habitable space, such as a study, playroom, bedroom or utility. The garage door is replaced with a wall and window, the floor is raised and insulated, and the walls and roof are brought up to building regulations.
How much does a garage conversion cost in Grantham?
In Grantham, a garage conversion typically costs £17,000–£28,500 for a single integral garage, including VAT at 20% (standard rate). We start from a UK-wide guide and adjust it for the East Midlands, where labour and materials are typically about 5% below average. Design, structural calculations and council fees are extra.
| Size or type | Guide range |
|---|---|
| A single integral garage | £17,000–£28,500 |
| Higher specification | £28,500–£35,500 |
The biggest cost drivers are:
- Whether planning permission is needed
- Single or double garage
- Foundations under the old door opening
- Integral, attached or detached
Use the guide price tool to see how size and specification change the figure, then ask for a written, itemised quote.
Do you need planning permission for a garage conversion in Grantham?
Before anything is built in Grantham, we confirm which approvals apply in England. In England converting an integral or attached garage usually does not need planning permission, unless a condition on the house removed permitted development rights (common on estates built in recent decades) or the house is listed. Building regulations approval is always needed.
Building regulations approval comes from the council’s building control service or a registered building control approver. The work is inspected at key stages, such as foundations, drainage and insulation, and a completion certificate is issued at the end.
Our first visit includes a check of your planning history, so you know the route before paying for drawings.
What we handle
Handled as part of most garage conversions:
- Wall and ceiling insulation
- Foundation check under the garage door opening
- Building control completion
- Floor raised with insulation and damp-proof membrane
- Drawings and building control application
- Electrics, heating and plastering
How long does it take?
The build itself usually takes 3 to 6 weeks on site. Design and approvals come first and typically take 6 to 12 weeks, depending on the approval route.
Building in Grantham
The East Midlands has a mix of red-brick terraces, inter-war semis and newer estates, so rear extensions and garage conversions are common projects.
Our Grantham coverage includes postcode districts NG31, and we also work in nearby places such as Newark on Trent, Melton Mowbray and Oakham.
How it works
- 01
Free visit
We look at the property, talk through what you want and measure up. There is no charge and no obligation.
- 02
Design and fixed quote
Drawings, structural calculations and an itemised, fixed price for the agreed specification.
- 03
Approvals
Planning or permitted development confirmation, building regulations and any party wall matters.
- 04
Build and sign-off
We run the build to a written programme and hand over the completion certificate.
Questions about garage conversions in Grantham
How much does a garage conversion cost in Grantham?
In Grantham, a garage conversion typically costs £17,000–£28,500 for a single integral garage, including VAT at 20% (standard rate). Your fixed price depends on the survey and drawings.
Can a detached garage be converted?
Yes, but using it as separate living accommodation may need planning permission.
Will losing the garage affect parking?
Councils sometimes object if on-street parking is under pressure. We check local parking standards.
Can the floor be level with the house?
Yes. The garage floor is raised and insulated to match the house floor level.
Do you build garage conversions in Grantham?
Yes. We build garage conversions across Grantham, including postcodes NG31. Every project starts with a free home visit.